Used engine oil

I was thinking of impoverished Mexicans, not loco gringos.

n Mexico, they brush it on exposed, unpainted wood as a wood preservative and termite cure…It seems to work quite well for that…

I am writing from Mexico, and that one is new to me. I do see them use it on boards they use as forms to make the reinforced concrete beams for houses. They need to oil the boards so they can remove them after the concrete sets up nicely.

Don’t we get a lot of drinking water from wells? Don’t we get our oil from wells? How does the EPA keep the oil and water seperated down there?